To learn more about battling cold weather, read the Winter guide.Wind, Hail, and Fog Wind can appear any time, and will activate certain objects like flags to blow.Weather is dependent on the temperature, less so than the current Season, much as it is in the real world.
If a Sim wants to go to the beach and not get burned, they can use the new Sun Parasol. The simplest way to beat the heat is to head indoors as all buildings are climate-controlled. Rain Rain gets Sims a soaked moodlet, at least those without an Umbrella.
Umbrellas can be bought under Outdoor Activities in Buy Mode's Outdoors tab.
Fairies can use the Weather Stone to to bring a reviving rain that will water plants, fertilize them and take care of any weeding that needs to be done.
Vampires can use it to conjuer an Eclipsing Fog that will guarantee they can drink from or turn Sims.
An Allergy shot at the hospital will clear up the ailment and let your Sim carry on with their life.